Author(s): Myung Eun Lee; Il Won Seo
Linked Author(s): Il Won Seo
Keywords: 2D pollutant transport model; Advection-dispersion equation; SUPG method; Han River; Tidal flow
Abstract: Pollutant transport in Han River, which is one of the most important rivers in Korea, was studied using the 2D advection-dispersion model developed in this research. The numerical model was developed based on the streamline-upwind Petrov-Galerkin (SUPG) in which finite element grid was used in order to treat the complex geometry of the natural water bodies. Velocity fields for input data of pollutant transport simulation were obtained using 2D hydrodynamic model RMA2. The pollutant transport simulations in the steady state flow and in the tidal currents were carried out to analyze the effect of tidal currents on the 2D concentration distribution in the application region. The simulation results show that during the increasing datum period in the tidal condition, very large recirculation zones occurs, and water flows in the upstream direction. Therefore, in the tidal currents, the polluted water goes back and forth along the variation of flow direction. As a result of this movement of pollutant, the oscillation of concentration in time appears which reflect the significantly complex periodic variation of flow pattern with large circulations.